cmd_clear 
     cmd_read 
     cmd_update 
     cmd_write 
     td_addchangeint 
     td_changenum 
     td_changestate 
     td_eject 
     td_format 
     td_getdrivetype 
     td_getgeometry 
     td_getnumtracks 
     td_motor 
     td_protstatus 
     td_rawread 
     td_rawwrite 
     td_remchangeint 
     td_seek